Enter the total resistance of the conductor and its length into the calculator to determine the ohms per foot. This calculator helps in evaluating the resistance per unit length of an electrical conductor.

Ohms Per Foot Formula

The following formula is used to calculate the ohms per foot of a conductor.

Ω/ft = R / L


  • Ω/ft is the ohms per foot
  • R is the total resistance of the conductor (ohms)
  • L is the length of the conductor (feet)

To calculate the ohms per foot, divide the total resistance of the conductor by its length in feet.

What is Ohms Per Foot?

Ohms per foot is a measure of the electrical resistance of a conductor per unit length. It is a critical parameter in electrical engineering, used to determine how much resistance an electrical wire or cable has, which affects how much current it can safely carry and how much power will be lost as heat. The lower the ohms per foot, the better the conductor is at carrying electrical current without significant losses.

How to Calculate Ohms Per Foot?

The following steps outline how to calculate the Ohms Per Foot.

  1. First, determine the total resistance (R) of the conductor in ohms.
  2. Next, determine the length (L) of the conductor in feet.
  3. Next, gather the formula from above = Ω/ft = R / L.
  4. Finally, calculate the Ohms Per Foot (Ω/ft).
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Total resistance (R) = 5 ohms

Length of conductor (L) = 50 feet